1. Field of the Invention
The present invention relates to an exercise support device, an exercise support method, and an exercise support program. Specifically, the present invention relates to an exercise support device, an exercise support method, and an exercise support program by which the motion status (exercise status) of a human body at the time of exercise can be precisely grasped to be determined and improved.
2. Description of the Related Art
In recent years, because of rising health consciousness and rising interest in participation in races, more and more people are performing daily exercises, such as running, walking, and cycling, to maintain their wellness, improve their health condition, or participate in races.
These people are very conscious of and interested in measuring various biological information and exercise information and recording the measurement results in order to grasp their own health conditions and exercise status and achieve efficient and effective training.
As an item to be measured for the above-described purposes, a foot landing period and a foot lifting period while exercising (while running) have been conventionally known.
Here, the foot landing period can serve as, for example, a guideline for estimating the fatigued state of a human body or a guideline for recognizing whether the way of running such as “pitch running” or “stride running” is being appropriately performed. Also, it is possible to calculate a gait, a moving speed, a travelling distance, an energy consumption amount, and the like based on this foot landing period.
As a method for calculating a foot landing period while exercising, various methods have been proposed. In one of these methods, a force plate, which is a mechanical measurement device, is stepped while running, and a foot landing period is calculated from a period of time in which force is exerted. In another method, a foot landing period is calculated from moving images captured by a high-speed camera. In still another method, a foot landing period is estimated by a motion sensor being worn on a foot.
For example, the average value of foot landing periods can also be calculated by positive and negative spikes representing an instant when a foot of the user lands on the ground and an instant when the foot of the user takes off from the ground being detected based on a signal waveform obtained by an accelerometer while exercising and a time interval between these spikes being measured, as described in Japanese Patent Application Laid-Open (Kokai) Publication No. 2009-160392.
Among the various methods for calculating a foot landing period, a foot landing period can be relatively accurately calculated in the method using a force plate and the method using a high-speed camera. However, devices for these methods are bulky and expensive. Therefore, they are available only in part of educational or gymnastic organizations, and cannot be used by ordinary people. Also, these devices can obtain data of only several footsteps within a narrow range where the force plate is installed or the range of the imaging field of the high-speed camera.
On the other hand, the method where a motion sensor is worn on a foot is advantageous in that information regarding lower limbs can be exclusively obtained. However, other information such as the motion status of the upper body and a heart rate while exercising cannot be simultaneously obtained. Accordingly, when these pieces of information are to be acquired, a sensor or the like has to be further worn on a different body part.
Also, according to verification by the inventor, in the calculation method of the above-described technique based on acceleration data, foot landing timing and takeoff timing cannot be precisely detected and therefore foot landing periods cannot be accurately calculated. This verification result will be specifically described in embodiments described further below.